Agreement Isn't Always Good: A Response Surface Analysis on Parent–Child (In)congruence in Intimacy and Conflict

Background Parent–child agreement in perceptions, especially shared perceptions of high intimacy, is often regarded as beneficial, but whether such congruence is uniformly beneficial may depend on individuals' developmental stages and cultural contexts. Objective To examine how parent–child congruence and incongruence in perceived intimacy and conflict relate to Chinese emerging adult children's romantic relationship satisfaction and life satisfaction. Methods We adopted a multi‐informant survey design and applied polynomial regression and response surface analysis (RSA). The sample consisted of 438 Chinese parent‐emerging adult child dyads. Results (A) Parent–child congruence in intimacy was negatively and linearly associated with romantic relationship satisfaction, but showed a U‐shape with life satisfaction. (B) Incongruent intimacy was not significantly associated with romantic satisfaction but showed a U‐shape with discrepancy magnitude for life satisfaction. (C) Congruent conflict was negatively and linearly associated with romantic satisfaction and U‐shaped for life satisfaction. (D) Incongruent conflict was significantly negatively associated with romantic satisfaction but not associated with life satisfaction. (E) Romantic relationship satisfaction mediated the associations between parent–child (in)congruence in intimacy/conflict and emerging adult children's life satisfaction. Conclusion The benefits of parent–child perceptual congruence are not universal; they may depend on individuals' developmental stages and cultural contexts. Implications These findings highlight the value of using RSA to capture nonlinear and asymmetric patterns in multi‐informant family research. Practical strategies are provided for promoting emerging adults' well‐being in the Chinese context.